I recently upgraded to BIOS 1903 and there are two issues that have come to my attention; one second-hand and the other first-hand.

The second-hand issue is noted here. This person found that EeeControl would not work under 1903 and backed up to BIOS 1703.

The first-hand issue I realized just in the past two days. When my system would go into screensaver mode, no matter what I'd do, the screensaver process would not end. The screensaver would stop its animation, but when I logged in via SSH under Putty (the only way I could get into the system), I had to kill -9 <pid> of the process skyrocket; my screensaver choice. Once I did that, I could get into the password-unlock screen.

I have backed my BIOS to 1902 and have re-tested the issue ... and my system is running properly, again; thankfully!

HTH!
Alan

hmm strange but good to know.
but why did you upgrade the bios ??

No particular reason

I upgraded the BIOS to 2001 and the screensaver issue that occurred under 1903 is not present.

I cannot speak for EeeControl, though. I don't have/use that.

Eeepc 901, jaunty ubuntu. 2 Mb ram from 1903-mode (working well) to 2001 new bios.
Boots ok after changing enable camera and wifi.
Eeecontrol-tray 0.92 working perfect. Wifi connections working...I don't know the differences with the new 2001 bios (only has a very intersting name: 2001 (as kubrick movie)